How Can I Get The Bulk Of Data From Sqldatabase To Textfile With Out Using Any Loop

Use an SqlDataAdapter to read it into a DataTable:

using (SqlConnection con = new SqlConnection(strConnect))
    {
    con.Open();
    using (SqlDataAdapter da = new SqlDataAdapter("SELECT MyColumn1, MyColumn2 FROM myTable WHERE mySearchColumn = @SEARCH", con))
        {
        da.SelectCommand.Parameters.AddWithValue("@SEARCH", myTextBox.Text);
        DataTable dt = new DataTable();
        da.Fill(dt);
        ...
        }
    }

You can then use whatever you want to save the datatable as a text file: Writing a DataTable to a CSV file[^] is one way, but there are loads of other depending on what your text file shoudl contain.